1. Technical Field
The present invention relates to a liquid discharging apparatus and a discharge state determination method of liquid in a liquid discharging apparatus.
2. Related Art
A liquid discharging apparatus such as an ink jet printer executes a printing process by forming images on a recording medium by discharging a liquid such as an ink, with which a cavity (a pressure chamber) of a discharge section is filled, as a result of displacing a piezoelectric element provided in the discharge section due to driving the piezoelectric element using a driving signal.
In this kind of liquid discharging apparatus, there are cases in which a printing process is performed using a pigment ink and a dye ink. For example, JP-A-2007-196593 proposes a technique that executes a printing process by adopting a pigment ink that is suited to text character printing, as a black ink, and adopting a dye ink that is suited to the printing of a clear color image, as a color ink. In addition, JP-A-2003-096369 discloses a printing process in which a pigment ink and a dye ink are used in combination.
Given that, in a liquid discharging apparatus, there are cases in which a discharge abnormality, in which it is no longer possible to normally discharge a liquid from a discharge section, occurs as a result of thickening of the liquid inside a cavity, the incorporation of an air bubble in the cavity, or the like. Further, when a discharge abnormality occurs, it is no longer possible to correctly form intended dots, which are formed on a recording medium by a liquid that is discharged from a discharge section, and therefore, the image quality of an image that the liquid discharging apparatus forms on the recording medium, is reduced.
In JP-A-2004-276544, a technique that prevents a reduction in image quality due to a discharge abnormality by detecting residual vibrations that occur in a discharge section after displacing a piezoelectric element through driving thereof using a driving signal, and determining a discharge state of a liquid in the discharge section on the basis of the characteristics of the residual vibrations such as the period length and amplitude of the residual vibrations, is proposed.
In a case in which a liquid discharging apparatus is capable of executing a printing process using a plurality of types of ink, and in particular, in a case in which a liquid discharging apparatus is capable of discharging a pigment ink and a dye ink in the manner disclosed in JP-A-2007-196593 and JP-A-2003-096369, the characteristics of residual vibrations that occur in a discharge section that discharges a pigment ink, and the characteristics of residual vibrations that occur in a discharge section that discharges a dye ink differ. Therefore, in a case in which the type of ink that each discharge section is filled with is not taken into consideration, there is a problem in that the accuracy of determination of the discharge state of liquid in a discharge section, is reduced.